Real Fancy's pool & spa filter is dedicated to bringing purer and cleaner water to your pool. You can experience the joy of being in the water with more peace of mind. Replacement Filter.Our filter is compatible with Caldera 50, Caldera Spas, Unicel C-7350, 1019401, 73532, PCD50N, Filbur FC-3963. All manufacturers' names and part numbers are used for compatibility information only. Dimensions.Length:10-3/4"; Outer Dimension:7"; Top: semi-circular handle; Bottom: 2-11/16" opening?Filtration Area: 50 sq.ft. The spa filter has ultra-high water filtration capacity. It can effectively remove hair, leaves, dust, sediment, sand, and other fine particles, easily remove debris, and always keep the water clean. The hot tub spa filter is washable and reusable. Simply remove and rinse with water, and the cleaned filter will be a new one. It is recommended to clean the filter every two weeks to fully utilize its performance.